Sutili F J, Silva L de Lima, Gressler L T, Gressler L T, Battisti E K, Heinzmann B M, de Vargas A C, Baldisserotto B
Departamento de Fisiologia e Farmacologia, Universidade Federal de Santa Maria, Santa Maria, Brazil.
Curso de Farmácia, Universidade Regional Integrada do Alto Uruguai e Missões, Santiago, Brazil.
J Appl Microbiol. 2015 Jul;119(1):47-54. doi: 10.1111/jam.12812. Epub 2015 Apr 20.
The aims of this study were to investigate the in vitro antibacterial activity of the essential oils (EOs) of Hesperozygis ringens (HREO), popularly known as 'espanta-pulga' and two different species of basil, Ocimum gratissimum (OGEO) and Ocimum americanum (OAEO), as well as, the potential of these products to be used in silver catfish (Rhamdia quelen) infected with Aeromonas hydrophila.
OGEO and HREO showed better antibacterial activity in vitro. Subinhibitory concentrations of all EOs inhibited haemolysis caused by Aer. hydrophila in fish erythrocytes (100% reduction for OAEO at 100 μg ml(-1) and more than 90% for HREO and OGEO at 150 μg ml(-1) ). However, OAEO and HREO showed the best survival results (75 and 70% respectively) after their use as treatment (therapeutic baths-1 h daily/5 days) in silver catfish experimentally infected with Aer. hydrophila. A second in vivo assay using healthy fish was conducted to verify the potential of the EOs (preventive baths-1 h daily/5 days) to promote fish survival. Fish exposed to HREO and OAEO and their diluent (ethanol) showed significant lower haematocrit values and higher complement system activity compared to control. Plasma cortisol level was significantly higher in the groups exposed to both EOs. There was no significant difference in survival of silver catfish challenged with Aer. hydrophila after preventive baths with HREO, OAEO and control group.
All tested EOs showed in vitro antibacterial properties against Aer. hydrophila and HREO and OAEO showed potential to be used in the treatment of infected fish.
These products can be used in aquaculture as therapeutic and prophylactic agents against fish pathogens, with antimicrobial and/or immunostimulant properties.
本研究旨在调查通常被称为“espanta - pulga”的环叶香茅（Hesperozygis ringens）精油（HREO）以及两种不同罗勒属植物，即丁香罗勒（Ocimum gratissimum，OGEO）和美洲罗勒（Ocimum americanum，OAEO）的体外抗菌活性，以及这些产品用于治疗感染嗜水气单胞菌的蟾胡子鲶（Rhamdia quelen）的潜力。
OGEO和HREO在体外表现出更好的抗菌活性。所有精油的亚抑菌浓度均抑制了嗜水气单胞菌在鱼红细胞中引起的溶血（OAEO在100 μg/ml时溶血减少100%，HREO和OGEO在150 μg/ml时溶血减少超过90%）。然而，在对实验感染嗜水气单胞菌的蟾胡子鲶进行治疗（治疗浴 - 每天1小时/5天）后，OAEO和HREO显示出最佳的存活结果（分别为75%和70%）。进行了第二项使用健康鱼的体内试验，以验证精油（预防性浴 - 每天1小时/5天）促进鱼存活的潜力。与对照组相比，暴露于HREO和OAEO及其稀释剂（乙醇）的鱼的血细胞比容值显著降低，补体系统活性更高。暴露于两种精油的组中血浆皮质醇水平显著更高。在用HREO、OAEO进行预防性浴后，受到嗜水气单胞菌攻击的蟾胡子鲶的存活率与对照组之间没有显著差异。
所有测试的精油均表现出对嗜水气单胞菌的体外抗菌特性，HREO和OAEO显示出用于治疗感染鱼的潜力。
这些产品可作为具有抗菌和/或免疫刺激特性的治疗和预防剂用于水产养殖，对抗鱼类病原体。
